For example, as shown in Patent Document 1 (Japanese Patent Application Publication No. 2004-282989), an axial air-gap electronic motor is configured so that a rotor is arranged opposedly on one or both of side surfaces of a stator with a predetermined gap therebetween, and is characterized in that the thickness thereof in the rotating shaft direction can be reduced, namely, can be made flat as compared with a radial gap electronic motor of an inner rotor type etc.
Also, since the facing area of the rotor and the stator and the winding occupying rate of a coil are improved, the magnetic flux is directed in the axial direction, so that high efficiency and high output can be achieved.
The axial air-gap electronic motor described in Patent Document 1 is constructed so that the stator is formed by joining a plurality of fan-shaped core members in a ring form. According to this construction, a coil is wound on one core member in advance, and the core members are joined in a ring form and wired, by which the stator can be formed easily.
However, in such a stator construction, since each core member, which has conventionally been in a separate state, is set on a wire winding device one by one so that a coil is wound thereon, the work for preparing core members necessary for assembling one stator requires much labor and time.
Also, after the coil has been wound on the core member, the coil pulled out of each core member for each phase must be connected, which presents a problem in that wire connecting work and transition wire processing also require much labor and time.